Backhoes for ditch digging machines



2 Sheets-Sheet '1 u, 5 m m m 5 MW F 2 T. n m f E f V 0 x Q k N u w a 0 5 n IQ M r yr Ll M r EWMHW 4 7 June 20, 1961 W. J. BRADLEY BACKHOES FOR DITCH DIGGING MACHINES Filed Jan. 19, 1959 u, @NW W 8 1 w 8 w 0/ 3\\\\\\ 1|. w :5 k K (v 2 5 1 Z l 3 1 5 8 u w a 0 @III lllll k! LO L II In? I c F June 20, 1961 w. J. BRADLEY BACKHOES FOR DITCH DIGGING MACHINES 2 Sheets-Sheet 2 Filed Jan. 19. 1959 BACKHOES FOR prion DIGGING MACHINES William .1. Bradley, North Hollywood, Calif., assignor to Earth Equipment Corp, Los Angeles, Calif., a corporation of California Filed Jan. 19, 1959, Ser. No. 787,547 Claims. (Cl. 214-138) This invention relates to backhoes for ditch digging machines, and included in the objects of this invention are:

First, to provide a backhoe which is adapted for attachment to various types of earth-moving machines having a boom capable of tiltably supporting an operating tool, and having means for tilting the tool, for example, Patents Nos. 2,651,424, 2,678,140, 2,725,996, 2,755,946, 2,788,143, and others.

Second, to provide a backhoe which incorporates a particularly compact operating means wherein a backhoe tool may be extended and retracted, as Well as pivoted, about two axes.

Third, to provide a backhoe wherein the power units for effecting pivotal movement of the backhoe tool about a longitudinal and a transverse axis is contained within a reciprocable tubular shaft structure.

Fourth, to provide a backhoe wherein the manipulating mechanisms are confined within the projected area of the backhoe tool so as to enter readily any excavation created by the tool.

With the above and other objects in view, as may appear hereinafter, reference is directed to the accompanying drawings in which:

FIGURE 1 is a side view of the backhoe with the means of its connection to a boom of a tractor unit being shown fragmentarily, and indicating by broken lines a displaced position of the bucket member;

FIGURE 2 is an enlarged, fragmentary, longitudinal, sectional view taken through 22 of FIGURE 1 showing the proximal end of the structure;

FIGURE 3 is a fragmentary, longitudinal, sectional view taken through 33 of FIGURE 2;

FIGURE 4 is an enlarged, fragmentary, partial elevational, partial sectional view showing the distal end of the structure;

FIGURE 5 is a fragmentary, longitudinal, sectional view thereof taken through 55 of FIGURE 4;

FIGURE 6 is a transverse sectional view through 6-6 of FIGURE 2;

FIGURE 7 is a transverse sectional view through 77 of FIGURE 4.

The backhoe structure includes a saddle frame 1 which is U-shaped in cross section and provided with side flanges 2 which are adapted to be connected by pivot pins 3 and 4 to a boom and a piston rod 6. The boom 5 is part of a conventional mobile unit in the nature of a tractor and is adapted to be raised and lowered in a conventional manner. The piston rod 6 extends from a conventional hydraulic power unit mounted on the boom 5.

The machine with which the present invention cooperates may be of the type more fully disclosed in the aforementioned patents and forms no part of the present invention. It is merely sufiicient for the operation of the present invention that the saddle frame 1 be capable of pivotal movement about the end of the boom 5, this being accomplished by the extension and retraction of the piston rod 6.

The side flanges 2 of the saddle form 1 are provided with aligned pairs of rollers 7. Longitudinally movable between the side flanges 2 is a tubular shaft structure 8 having channel tracks 9 formed in its opposite side walls to receive the rollers 7 so that the shaft structure 8 is limited to a longitudinal or reciprocal movement with respect to the saddle frame 1.

States Patent C) F ice Mounted on the saddle frame 1 is a bracket 10, and a similar bracket 11 is mounted at the extremity of the shaft structure 8. A hydraulic power unit comprising a power cylinder 12 and rod 13 is joined to the brackets 10 and 11 so that on extension and retraction of the rod 13 the shaft structure 8 is reciprocated relative to the saddle frame 1.

The distal end of the shaft structure 8, from the bracket 11, is provided with an internal journal 14 in the form of a cylinder having relatively thick walls. The ends of the journal 14 are reduced externally. Fitted within the shaft structure 8 are retainer rings 15 and 16 which secure the journal 14 within the shaft structure 8 and permit rotation of the journal 14 with respect to the shaft structure 8. The journal 14 is provided with a central bore 17, and its side walls are provided with a pair of helical cam slots 18. These slots have, preferably, a circumferential extent slightly less than Formed in the side walls of the tubular shaft structure 8, opposite the journal 14, is a pair of diametrically opposed axial slots or guide tracks 19. Extending diametrically through the helical cam slots 18 of the journal 14 and into the axial slots 19 is a cross pin 20. Rollers 21 and 22 are journaled on the extremities of the cross pin 20 and ride, respectively, in the cam slots 18 and axial slots 19.

The cross pin 20 passes through a ball head 23 which fits within the bore 17. The head 23 is connected to a rod 24 of a hydraulic power unit which also includes a power cylinder 25. The piston rod 24 and power cylinder 25 extend axially inwardly from the extremity of the shaft structure 8. The end of the power cylinder 25 remote from its rod 24 is anchored by means of a cross pin 26, the extremities of which are secured in the side walls of the shaft structure 8. Reciprocation of the rod 24 causes the rollers 21 and 22 to move in their respective slots 18 and 19 and eflect rotation of the journal 14 about the longitudinal axis of the shaft structure 8 within the limits provided by the helical slots 18.

The journal 14 protrudes from the distal end of the shaft structure 8 and is externally screw-threaded to receive a crosshead 27 which in turn receives a transversely extending pivot pin 28. The extremities of the pivot pin 28 are pivotally connected to brackets 29 which in turn are secured to a bucket 30. The bucket 30 may be conventional and be in the form of a half cylinder with closed ends. The axis of the pivot pin 28 is located parallel to but offset from the center of the semicylindrical bucket 30.

The circumferential extremity of the bucket 39, remote from the pivot pin 28, is provided with suitable teeth 31. The circumferential extremity of the bucket nearest the pivot pin 28 is provided with brackets 32 which may be connected with the brackets 29 by means of brace links 33. Pivotally connected to the brackets 32 is a pm'r of struts 34 which diverge and extend toward the saddle frame 1.

Fitted on the tubular shaft structure 8 adjacent the saddle frame 1 is a thrust bearing ring assembly 35. The ring assembly includes an outer or rotatable race 36 having diametrically outwardly extending journal studs 37 which receive the adjacent ends of the struts 34. The thrust bearing ring assembly 35 also includes an inner or fixed race 38 which is slidable on the shaft structure 8. The inner race 38 is restrained from rotation by a cross pin 39 which extends diametrically through the shaft structure 8, the shaft structure being provided with longitudinal slots 40 to permit longitudinal movement of the cross pin 39 and the thrust bearing ring assembly 35.

The cross pin 39 is carried by a crosshead 41 which is attached toa rod 42 which extends longitudinally within the shaft structure 8 toward the end remote from the bucket 30. The rod 42 constitutes part of a hydraulic power unit which also includes a power cylinder 43. The power cylinder 43 is anchored at its end remote from the rod 42 by means of a cross pin 44 secured to the side walls of the shaft structure 8.

The power cylinders 25 and 43 within the tubular shaft structure 8 are provided with flexible pressure fluid supply lines 45 which extend axially through the shaft structure 8 to its end remote from the bucket 30. Other supply lines 46 extend from the power cylinder 12. The flexible pressure fluid supply lines extend to a conventional source of pressure fluid carried by the machine on which the backhoe structure is mounted, suificient slack being provided to permit the necessary reciprocation of the shaft structure 8 relative to the saddle frame 1.

Operation of the backhoe structure is as follows:

The saddle frame 1 is connected in a conventional manner to a machine having a suitable boom and power unit so that the saddle frame may be raised, lowered, tilted, or otherwise manipulated in the conventional manner.

The shaft structure 8 may be extended or retracted at will by operation of the power cylinder 12 and rod 13. The bucket 30 may be pivoted about the axis of the pin 28, that is, an axis transverse to the shaft structure, by means of the power cylinder 43 and struts 34. In addition, the bucket may be turned about the axis of the shaft structure 8 by means of the power cylinder 25, rollers 21 and 22, and the cooperating helical and axial slots 18 and 19. By reason of these movements, which may be performed simultaneously or in sequence, the bucket 30 may be readily manipulated, not only to perform digging operations but also to lift material for deposit in a truck or along the side of the ditch or other excavation.

It will be observed that the mechanism which controls the bucket 30 is particularly compact so that the bucket may be maneuvered into difficult and cramped regions which would otherwise be inaccessible. It will be also observed that by reason of the thrust bearing ring assembly 35, tilting movement of the bucket 30 about the transverse axis of the pivot pin 28 may be accomplished irrespective of the position of the bucket circumferentially of the longitudinal axis of the shaft structure 8.

While a particular embodiment of this invention has been shown and described, it is not intended to limit the same to the exact details of the construction set forth, and it embraces such changes, modifications, and equivalents of the parts and their formation and arrangement as come within the purview of the appended claims.

What is claimed is:

1. An operating structure for digging tools, comprising: a supporting and guiding means; a tubular shaft structure reciprocably carried by said supporting and guiding means; means for effecting reciprocation of said shaft structure; means within the distal end of said shaft structure journallin g said digging tool for movement about the longitudinal axis of said shaft structure; means within said tubular structure engageable with said journalling means to effect said movement of the digging tool; means for pivotably mounting said tool for movement about an axis transverse to said longitudinal axis; and means including a collar rotatably and longitudinally movable on said tubular structure, and a collar-reciprocating means within said tubular shaft structure for effecting pivoting of said digging tool.

2. A backhoe structure for ditch digging machines, comprising: a backhoe tool including digging teeth and a collector bucket; means for journaling said tool about a first axis; means for pivoting said tool about a second axis; a tubular shaft structure for receiving said journaling means; a first reciprocable power unit within said shaft structure; means including helical cam means for converting reciprocation of said first power unit into rotation of said journaling means; a second reciprocable power unit within said shaft structure; and means including a reciprocable and rotatable collar connected with said second power unit, and struts connecting said collar with said tool to effect pivotal movement of said tool.

3. A backhoe structure for ditch digging machines, comprising: a backhoe tool including digging teeth and a collector bucket; means for journaling said tool about a first axis; means for pivoting said tool about a second axis; a tubular shaft structure for receiving said journaling means; a first reciprocable power unit within said shaft structure; means including helical cam means for converting reciprocation of said first power unit into rotation of said journaling means; a second reciprocable power unit within said shaft structure; means including a reciprocable and rotatable collar connected with said second power unit, and struts connecting said collar with said tool to effect pivotal movement of said tool; means adapted for connection with said machine and arranged to support said shaft structure for reciprocation; and a third reciprocable power unit interconnecting said supporting means and said shaft structure.

4. A digging tool structure adapted for connection with a machine having a boom and a relatively reciprocable element, comprising: a shaft-supporting structure constructed and arranged for pivotal connection with said boom and said element to effect pivotal movement of said shaft-supporting structure; a tubular shaft structure reciprocably carried by said supporting structure; means for effecting reciprocation of said shaft structure; means within the distal end of said shaft structure journaling said digging tool for movement about the longitudinal axis of said shaft structure; means within said tubular structure engageable with said journaling means to effect said movement of the digging tool; means for pivotably mounting said tool for movement about an axis transverse to said longitudinal axis; and means including a collar rotatably and longitudinally movable on said tubular structure, and a collar-reciprocating means within said tubular shaft structure for effecting pivoting of said digging tool.

5. A backhoe structure adapted for connection to a machine having a boom and a relatively reciprocable element, comprising: a backhoe tool including digging teeth and a collector bucket; means for journaling said tool about a first axis; means for pivoting said tool about a second axis; a tubular shaft structure for receiving said journaling means; a first reciprocable power unit within said shaft structure; means including helical cam means for converting reciprocation of said first power unit into rotationof said journaling means; a second reciprocable power unit within said shaft structure; means including a reciprocable and rotatable collar connected with said second power unit, and struts connecting said collar with said tool to effect pivotal movement of said tool; a supporting means adapted for pivotal connection with said boom and a reciprocable element to effect pivotal movement of said supporting means; guide and track means incorporating said supporting means and shaft structure to permit movement of said shaft structure along its longitudinal axis; and a third power unit interconnecting said supporting means and shaft structure to effect reciprocation of said shaft structure.

References Cited in the file of this patent UNITED STATES PATENTS Re. 21,405 Stiehl Mar. 19, 1940 1,747,698 Clausen Feb. 18, 1930 2,476,249 Payne July 12, 1942 2,541,045 Ferwerda Feb. 13, 1951 2,594,720 Beck Apr. 29, 1952 2,725,996 Britton Dec. 6, 1955 2,822,094 Greer Feb. 4, 1958 2,831,589 Way Apr. 22, 1958 FOREIGN PATENTS 1,085,841, France Aug. 4, 1954 

